Thanks Chris, that does help a bit.
I started designing our obs a while back, initially based on a geodesic dome above a square room. Perceived difficulties attaching facets to the ring and slot frame as well as trying to get a stairway from a rectangular wall into a round aperture led me to settle on a ribbed structure with 24 gores on a round room with a spiral staircase.
Then I discovered IIS and saw your thread, wow
, that is what I had visualized.
To speed things up a bit we then settled on a sirius 3.5 dome only, but before all the ducks lined up a secondhand 3.5 came up which we grabbed.
The plan is to now elevate the sirius on the round room.
So our column will be probably be about the same height as yours. I would not have thought that the comparatively small load of a scope and mount would put much tension on a reinforced column suitable for supporting a shopping centre carpark !, although I have not yet waded through the calculations of an offset load.
I am hoping that the ascom-maxdome will handle scope/dome geometry as you can enter all sorts of offsets
Here is the evolution, Neil.